It is known that movable belt conveyor systems can be used for leaching oxidic copper ores by acid. Compaction by moving the belt conveyor system with moving caterpillars (endless tracks) is less critical here. In general, the conveying system for piling up a leach pad comprises a plurality of feed belts, a movable tipping belt and a stacking system with traveling trippers and a stacker or a tilting bridge.
Depending on the design embodiment of these belt conveyor systems, various moving devices may be provided for use for moving belt conveyor systems. Mainly caterpillar (endless track) tractors or bulldozers with laterally arranged moving heads are used for moving belt conveyor systems with belt-supporting structures standing on ground sleepers, which are connected to one another by one or two moving rails.
Such a belt-moving device, which comprises a caterpillar tractor as the basic device, on which a side boom with a roller head is arranged as a moving means, is known from the technical book Baumaschinen; Erdbau-und Tagebaumaschinen [Building Machinery; Earth-moving Machinery and Open Cast Mining Machinery], Verlag Vieweg, 1 st edition, 2002, page 369, Section 7.3.2 “Rückfahrzeug mit Rückkopf” [Moving Vehicle with Moving Head]. The belt conveyor system is grasped at a moving rail during the moving operation, raised on one side, pulled laterally and finally lowered again in the end position. A certain amount of moving is achieved by a plurality of partial moving operations. The moving device covers the entire length of the belt conveyor system during each partial moving operation. The head and rail stations with belt drive and a traveling tripper that is possibly present are moved by another auxiliary device, for example, a transport caterpillar because of their own heavier weight. Fine alignment of the belt-supporting structures is necessary at the end of each moving operation. This solution shown has the advantage that the belt section is lightweight and the caterpillar tractor can again be used for other tasks after the moving of the belt. However, the multiple moving of the moving device to and fro causes an additional compaction of the subsoil, which may even be useful, as, for example, in open cast mining in case of freshly deposited surfaces, but this may be undesired in case of traveling on a dump on which ore has been freshly dumped.
Furthermore, a belt conveyor system is known, which is equipped with caterpillar-type moving gears (endless track moving treads) and can thus perform the moving operation itself. It comprises a plurality of individual bridges, which are connected to one another in an articulated manner and can be moved on their caterpillar-type moving gears at right angles to the direction of delivery (technical journal Surface Mining, 2001, No. 2, page 248, title: “Dynamic Pad Reclaim and Stacking System”). The conveyor belt is guided continuously from the beginning to the end of the segments. The drive is accommodated in the last segment and the tensioning station in the first segment. A traveling tripper is arranged on the bridges movably over the entire length of the conveyor. The bridges must therefore be made sufficiently stable and provided with a roadway for the traveling tripper. This conveyor has a very heavy weight of its own, which acts on the subsoil via the caterpillar-type moving gears of the segments and thus compacts same, which may be undesired in certain cases, for example, when a dump is piled up for a certain leaching process.
Due to their heavy weight, the above-described movable belt conveyor systems are very expensive in case of great lengths.